**Enter the data.**- Type "
`x1`" in cell A1; then, in cells A2-A18, enter the Air Flow data from Table 4.8 (p. 150). - Type "
`x2`" in cell B1; then, in cells B2-B18, enter the Cooling Water Inlet Temperature data from the table. - Type "
`x3`" in cell C1; then, in cells C2-C18, enter the Acid Concentration data from the table. - Type "
`y`" in cell D1; then, in cells D2-D18, enter the Stack Loss data from the table.

*Screenshot:*- Type "
**Compute the multiple linear regression and display related plots.**- Select
**"Tools --> Data Analysis."** - In the dialog that follows, select
**"Regression"**from the list of options. - Click
**"OK."** - Fill out the resulting dialog box as follows:
Input Type Label Value **Input Y Range:**`$D$1:$D$18`**Input X Range:**`$A$1:$C$18`**Labels***checked***Constant is Zero***unchecked***Confidence Level***unchecked***New Worksheet Ply:***selected***New Worksheet Ply:****Residuals***checked***Residual Plots***checked***Standardized Residuals***checked***Line Fit Plots***unchecked***Normal Probability Plots***checked* - Click
**"OK."**

*Excel creates a new sheet in the workbook with the summary statistics, plots of residuals vs. x1, x2, and x3, and a normal probability plot.***Note:**you can resize all columns to fit their contents by selecting all the cells you want to resize, then selecting**"Format --> Column --> Autofit Selection."****Note:**you can move the charts as necessary by clicking a blank area in the chart and dragging it to a new location. Other changes can be made by double-clicking various elements in the charts.- Select